The long term objective of this project is to develop an animal model system to study viral induced degenerative changes in temporomandibular joints. This pilot study is designed to see if viral lesions can be induced in hamster temporomandibular joint tissues with a rat virus that is known to produce craniofacial and dental abnormalities in hamsters. Specifically, hamsters will be inoculated with rat virus and will be sacrificed at 14, 21, or 28 days post-inoculation. The temporomandibular joint tissues will be removed and then processed for light microscopic study. Representative tissue sections will be stained with hematoxyalin and eosin, Masson's trichrome, periodic acid Schiff's reagent or resorcin fuchsin in order to study the morphologic effects of the viral infection on the temporomandibular joint tissues. If the joint tissues are susceptible to the viral infection, then we plan to propose additional studies to determine the specific cells involved in the infection using DNA probes. In addition, future studies will employ autoradiographic and morphometric techniques to study the effects of the virus on collagen and elastin production and distribution. This approach may allow us to better understand the specific cells involved in the arthropathy that we hypothesize will result from viral infection.